Do we know how living beings get infected?

As in title - Is there somewhere a note/book/dialog with npc, that at least hints the spread of pestilence? We don’t know how Alden transformed, why Darak is seemingly human in first phase (despite being a literal tower compared to others), and then transforms into monster, how Lara was morphed with bear (maybe idea from Annihilation? Eaten = morhped). It would be interesting getting a cinematic of npcs getting infected, or even enemy like in Dead Space that could raise/infect corpses or living beings. Also, if pestilence spreads, then how e.g. in the Woods we have some infected rats, wolves, and others are seem fine?

Can’t say I’ve seen anything that describes this, in any dialogue. Some npc’s share that some loved ones have been taken, or they have seen the results of infection on others.

We probably need more of the story to shine a light on the workings of the Plague!

Silas